Author

Topic: Five R9 280X Power (Read 621 times)

hero member
Activity: 630
Merit: 502
February 27, 2014, 11:56:06 AM
#8
Go for LEPA 1600 it will power all your 5x 280x
They are not in stock anywhere in Canada.
hero member
Activity: 770
Merit: 500
February 27, 2014, 11:51:01 AM
#7
Go for LEPA 1600 it will power all your 5x 280x
hero member
Activity: 630
Merit: 502
February 27, 2014, 10:38:23 AM
#6
Would 2 750W Gold PSU or equivalent be sufficient for 5 undervolted R9 280X + motherboard on a 15A circuit?

answer is yes iif you don't overclock too much..
Hashrate would drop if core is overclocked more than 50MHz.
sr. member
Activity: 366
Merit: 250
February 27, 2014, 10:35:48 AM
#5
Would 2 750W Gold PSU or equivalent be sufficient for 5 undervolted R9 280X + motherboard on a 15A circuit?

answer is yes iif you don't overclock too much..
hero member
Activity: 630
Merit: 502
February 27, 2014, 10:03:21 AM
#4
I allowed 360 watt per card when I chose my psu's  I am running 6 R9 280x on 1 rig and 2 on another

So if you say 360w x 5 cards = 1800w plus what ever you will use for your cpu or ssd etc

If you take my rig that runs at 2000w and say 6/2000 = 333.333333 you could go 5 x 333.33333 = 1666.665watts

I have read that these cards will only pull 300 watts per card though, but my 6 card rig pulls ave 1950 - 2000watts, but I use an ssd drive and a 54watt cpu, and use powered riser cables.

Hope this helps, may be go with 2 x 850 psu's
Voltage in North America is between 110 and 120 so a 15A circuit have a max output of 1800W AC. I have heard of people running 4 280X on a 1200W PSU. Undervolting 5 cards will reduce the draw by 100W and in conjunction with 90% efficient PSUs, it should be at about 80-85% of 15A limit.
legendary
Activity: 854
Merit: 1000
February 27, 2014, 10:02:00 AM
#3
1500w total watts... for 5 280x, even undervolted you're sorta riding the line there.

280xs can and will ride up to 300w quickly.
newbie
Activity: 56
Merit: 0
February 27, 2014, 09:53:15 AM
#2
I allowed 360 watt per card when I chose my psu's  I am running 6 R9 280x on 1 rig and 2 on another

So if you say 360w x 5 cards = 1800w plus what ever you will use for your cpu or ssd etc

If you take my rig that runs at 2000w and say 6/2000 = 333.333333 you could go 5 x 333.33333 = 1666.665watts

I have read that these cards will only pull 300 watts per card though, but my 6 card rig pulls ave 1950 - 2000watts, but I use an ssd drive and a 54watt cpu, and use powered riser cables.

Hope this helps, may be go with 2 x 850 psu's
hero member
Activity: 630
Merit: 502
February 26, 2014, 08:21:28 PM
#1
Would 2 750W Gold PSU or equivalent be sufficient for 5 undervolted R9 280X + motherboard on a 15A circuit?
Jump to: